I really enjoyed this. There's a beautiful starkness to it, like the cold, windy seacoast you've described. Your characters are wonderfully drawn, in all their realistic awkwardness. The way you've written Marietta and her mother really nails that type of dynamic, where a child is having to take care of a parent emotionally whether they consciously know it or not. And her feelings for Cho just break my heart — I wonder if Cho had a sense of how much she meant to Marietta and how much it would have hurt her to be abandoned, and that's why she tried so hard to defend her?
It makes sense that Marietta and Milicent would be drawn to each other. They're both tremendously vulnerable, but not broken. They haven't closed off completely, they're still willing to risk getting hurt. You feel like these two might just save each other.